I'm really looking forward to this "Ra-Den". And also, i want to see Lei Shen Heroic. This patch is one of the best patches we had in years. Also Dinomancers.... how the fuck can someone hate this patch???

I don't know much about WoW lore, but here me out on this.
I'm also really high, so it may not make any sense.

According to this,http://www.wowpedia.org/Keeper_of_storms, the Keeper of Storms was worshipped by the Naga. Naga are essentially forces of the old gods.
The old gods are related here.
They created Ra-Den, who is a big bad mini-old god thing. And what remaining old god would have anything to do with the naga?
N'Zoth. Who is now deep under water. Who is around naga all the time.
IT MAKES SENSE!

TL;DR of my nonsense: Ra-Den is created by the old gods. N'Zoth is related. N'Zoth is the sha. N'Zoth is the end boss of this xpac and is corrupting Garosh.

Contradictions all around; A Sha is from the dead old god Ya'sharj including the 7th Sha. N'zoth has nothing or even remotely has nothing to do with ''Sha'' whatsoever The sha was unleashed after the death of Ya'sharj or whatever his name is creating the Sha and infesting the land.

Well, this looks like a Troll raid with some Mogu at the end. About time! Cataclysm had me worried with only having 5-mans.

As for Ra-Den, Raijin, also called Raiden, is a thunder god in Japanese mythology. We already knew that this guy was thunder-affiliated, but still, it tells you where his name came from - as well as every other character called "Raiden".

I like the idea of heroic-only endbosses, even if I never get to see them - hell, I've never seen Sinestra, or Ragnaros' heroic-only phase, but I still like how they were implemented. They're a great way to ensure that just getting to the encounter is a great feeling, as well as making sure that killing them at all is a great achievement. My last experience with that boss model was back when Ulduar was current, and getting to Algalon was awesome - even if I'm not 100% that the time limit was necessary.

The first 6 bosses look like Troll bosses, either being Trolls themselves or Troll creatures, with the possible addition of Durumu, which could be a some kind of Troll demon summon similar to what the Gurubashi used to have. I'd say at least half of the instance is Trolls, with 3 or 4 actual Mogu bosses, a Mogu construct and a Saurok. I'd consider all of those Mogu bosses for the same reason I count the multiheaded hydra as a Troll boss, though.

If you're at all wondering, I think the hydra is a Troll thing because of Gahz'ranka and all that.

Ra-den as heroic only boss? Hmm, interesting. I guess Ra-den will have some lore behind him. The boss seems to a mystery. I was hoping Thunder King to be the Heroic mode only boss, because he has been hyped up to be quite a bad ass.

I guess it wouldn't have been fair on the players who only have access to LFR/Normal modes to be gated from fighting the Thunder King after all the hype and lore that had been created for him. I don't have the time, skill or internet connection to be a hardcore raider and I certainly would have been disappointed if I was unable to fight Lei Shen in some form.
Either way. I'm looking forward to finding out who this Ra-den guy is and checking up on WoWprogress to see which guild is able to beat him first.

[Edit] Which reminds me. I thought Lei Shen was called The Thunder King because whenever he hurled his axe, it made a sound like crashing Thunder. But according to the dungeon journal, he is able to wield the power of electricity.
I'm sure it'll make for some interesting mechanics in the fight, but, come on! The name wasn't literal, guys!